Antitheft devices are designed to prevent unauthorized removal of an item from a secured location. These antitheft devices are commonly used, for example, in a retail sales environment such as a clothing store. The antitheft device is placed on an item such as an article of clothing and is removed by a store clerk after the customer has paid for the article. If someone tries to remove the article of clothing from the store without first removing the antitheft device, an alarm will sound or the store clerk will otherwise be notified.
Antitheft devices are often attached to the article of clothing using a magnetically releasable mechanism. This mechanism, a component of which may be, for example, a metal pin, locks the antitheft device onto the article of clothing such that it may only be removed when the antitheft device is in the presence of a magnetic field of sufficient strength and dimension to unlock the metal pin and allow its removal.
Magnetically releasable antitheft devices come in a variety of forms, each of which may require a slightly different magnetic “key” or “detacher” to unlock the device. For example, single pin or single clutch devices use a single locking pin which may be unlocked by a localized vertical magnetic field. By contrast a double clutch or double leaf spring devices may have two locations where a sufficient magnetic field is needed.
In order to prevent the theft of electronic media (e.g., DVDs, CDs, etc.) and other products, another type of antitheft device may be secured along the length of an edge of an electronic media case or other lockable unit. When in place, the antitheft device prevents the case from being opened to remove the media and will trip an alarm if removed from the store. To release this type of antitheft device, an elongated horizontal magnetic field may be used.
Because stores may use multiple types of antitheft devices, and because each antitheft device may require a different key or detacher to magnetically unlock and release it, it is desirable to have a single magnetic decoupling unit that can be used to magnetically release each of a plurality of common antitheft devices.